The Midnight Secret Lesson! The Dangerous Allurement of the Music Room!!
Kyoko bets with Miki that she will learn to play the piano in one week. Kyoko ends up going to secret midnight lessons thinking it's a dream. Her weariness begins to show and it concerns Miki and Nube.
Aired 01/03/1997EP 36 - The Midnight Secret Lesson! The Dangerous Allurement of the Music Room!!
1996
Jigoku Sensei Nube
Nube is a clumsy, easygoing, and very kind teacher, but he has a secret under his glove on the left hand. He has a monster hand, and he also has the ability to sense ghosts and evil spirits. So he protects his dear students from these evil spirits with his monster hand, proving to be very powerful.
(Source: Anime News Network)